Pallets have traditionally been formed of wood. Wood pallets however have many disadvantages. For example, they are subject to breakage and they take up a considerable amount of valuable floor space in the warehouse when they are not in use. They are also difficult to maintain in a sanitary condition, thus limiting their usability in applications where sanitation is important, for example, in food handling application.
In an effort to solve some of the problems associated with wood pallets, plastic pallets have been employed with some degree of success. In one generally successful form of plastic pallet design, a twin sheet construction has been used in which upper and lower plastic sheets are formed in separate molding operations and the two sheets are then selectively fused or knitted together in a suitable press to form a reinforced double wall structure. Whereas these twin sheet plastic pallets are generally satisfactory, they tend to be more expensive than comparable wood pallets and, in particular, their relatively higher cost has precluded their use in one-way applications where the pallet, after fulfilling an initial shipping or material handling assignment, is not reused but rather is destroyed or recycled after the single use.